Pay-per-view television programming has been available to cable television subscribers in North America for more than ten years. However, due to many practical difficulties, pay-per-view programming has not been widely accepted.
In the early days of pay-per-view television, local cable television operators generally contacted a number of program suppliers, obtained copies of the programs and scheduled and delivered programming to subscribers on a pay-per-view basis in accordance with revenue splits negotiated with each supplier. The programming would generally be stored at the cable headend for playback on a number of possible sources, including video tape or video cassette recorders, video disc players and the like. The programming would be delivered, on a pay-per-view channel to subscribers possessing addressable cable equipment, in response to orders placed by the subscribers. Known addressable cable equipment include addressable cable converter systems, addressable cable interdiction systems and addressable tap or trap systems.
Eventually, "middleman" networks evolved to deal with the program suppliers and to make programming available to a multiplicity of cable operators. These pay-per-view networks originated scrambled satellite feeds for pickup by participating or affiliated cable operators. With satellite delivered programs, the creation of monthly programming schedules became necessary. The schedules rotated programming from a number of program suppliers through a number of available monthly time slots. The pay-per-view schedules which resulted were not unlike the schedules of monthly subscription pay television, except that programs were released by suppliers to pay-per-view networks a number of months before the same programs were available to monthly subscribers. Subscribers needed to overlay their personal schedules with that of the network in order to find a convenient time to buy. Fixed monthly schedules did not allow for variation of schedules in different communities or in response to viewer preferences.
Several pay-per-view systems are proposed in the patent literature. U.S. Pat. No. 4,381,522, issued April 1983, to Lambert discloses a television system of the first type described above. At the cable television headend there are a number of pre-loaded video tape, disc or film players which are actuated by a minicomputer to transmit television programming over a cable channel in response to a computer generated schedule. The schedule is generated in response to signals transmitted from home viewers by telephone.
There are difficulties with the Lambert system. While the schedule is responsive to viewers' preferences, the system cannot manage community pay-per-view television. As soon as the system has received a number of program requests for a particular start time equal to the number of channels available on the system for this type of programming, others wishing to use the system have to choose between watching a program (and a start time) chosen by someone else or submitting a personal request for future consideration. Such a system does not have the potential to maximize the number of users who would purchase pay-per-view programming. With program scheduling being determined on a first-come-first-served basis, callers requesting a program of interest to few others could determine what programs were playing at what times. Even though more people might be interested in viewing a different program at that time, the channel capacity or time slots available and the random nature of the scheduling would likely yield poor overall usage rates for the system.
U.S. Pat. Nos. 4,694,490, issued September 1987, 4,704,725, issued November 1987, and 4,965,825, issued October 1990, to Harvey et al. propose far-reaching systems for communicating programming. The systems utilize encrypted signals in broadcast programming, which signals include user specific information which can be displayed or used to control receiver apparatus at the user location. Although far reaching, many practical aspects of broadcast and receiving technology make implementation into existing television transmission systems problematic.
Another viewer specific broadcasting system is disclosed in U.S. Pat. No. 4,450,477, issued May 1984, to Lovett. The system is designed to allow viewers selective access to television information from large databanks on request. In response to viewers' requests to the cable headend station, a control station sends uniquely modulated carrier frequencies with the selected information to the individual viewer, whose television set is tuned to that carrier frequency. Here again, the system is not practical for pay-per-view television to a large community.